A number of containers, such as beverage containers, are configured to achieve easy opening, such as without the need for a can opener or other tool and preferably do not involve separation of any parts. One design factor of some importance to consumers is the pour characteristics of the container. In general, consumers prefer to use containers capable of providing a relatively high pour rate.
Additionally, it is believed consumers prefer containers that provide a smooth pour, i.e. a pour which is not characterized by a series of surges (which can cause splashing and/or can affect a beverage head, fizz or other carbonation). An observable interruption or uneven flow occurs as the contents of the beverage container is being dispensed resulting in disruption in pressure equalization between the inside of the can and the ambient atmosphere with prior designs. Prior attempts to alleviate uneven flow characteristics required additional vent openings to be formed through the lid structure of the container. Other prior methods utilize specialized pour opening geometries. The additional vent openings and/or specialized pour opening geometries present design complexity, additional cost, and leakage concerns.
In light of the above, a need exists for a container opening that allows the atmosphere to replace the dispensed contents of the container and results in uninterrupted flow of the content being dispensed.